I C Engine (Set 1) | Multiple Choice Questions

1. In a typical medium speed 4-stroke cycle diesel engine the inlet valve

Opens at 20° before top dead center and closes at 35° after the bottom dead center

Opens at top dead center and closes at bottom dead center

Opens at 10° after top dead center and closes 20° before the bottom dead center

May open or close anywhere

2. The operation of forcing additional air under pressure into the engine cylinder is known as

Supercharging

Carburetion

Turbulence

Delay period

3. Compression ratio of I.C. Engines is

The ratio of volumes of air in cylinder before compression stroke and after compression stroke

Volume displaced by piston per stroke and clearance volume in cylinder

Ratio of pressure after compression and before compression

Swept volume/cylinder volume

4. The air standard efficiency of an I.C. engine is given by (where r = Compression ratio, and γ = Ratio of specific heats)

1 - r^{γ - 1}

1 + r^{γ - 1}

1 - (1/r^{γ - 1})

None of these

5. Pick up the wrong statement about supercharging

Supercharging reduces knocking in diesel engines

There can be limited supercharging in petrol engines because ofdetonation

Supercharging at high altitudes is essential

Supercharging results in fuel economy

6. The theoretically correct air fuel ratio for petrol engine is of the order of

6 : 1

9 : 1

12 : 1

15 : 1

7. Number of working strokes per min. for a four stroke cycle engine are _________ the speed of the engine in r.p.m.

Equal to

One-half

Twice

Four-times

8. In an internal combustion engine, the process of removing the burnt gases from the combustion chamber of the engine cylinder is known as

Scavenging

Detonation

Supercharging

Polymerisation

9. In the opposed piston diesel engine, the combustion chamber is located

Above the piston

Below the piston

Between the pistons

There is no such criterion

10. The ignition of the charge by some hot surface within the engine before the passage of spark is called

Pre-ignition

Detonation

Ignition delay

Auto-ignition

Internal Combustion Engine (Set 1)

Multiple Choice Questions